1. Field of the Invention
The present invention relates to an optical disk recorder, an optical disk player, and a combined apparatus of an optical disk recorder and player, which record or reproduce a video signal by coding and decoding in a highly efficient manner and to an optical disk recorded by the optical disk recorder.
2. Description of the Prior Art
FIG. 1 is a block diagram of a prior art recorder and FIG. 2 is a block diagram of a prior art player. In FIG. 1, a block dividing circuit 102 divides video data into very small blocks composed of a plurality of picture elements which are changed in order using a memory. An orthogonal transformer 103 transforms the data orthogonally, for example, by Discrete Cosine Transformation (DCT) for every block . A quantizer 104 quantizes each coefficient after orthogonal transformation. Also provided is a variable length encoder 105 using Huffman encoding. An error detection and correction code adding circuit 112 adds parity for detecting and correcting errors to the data after encoding. A modulator 113 converts the encoded data into a data row, which is matched to the optical disk.
In FIG. 2, a reproducing head 117 reproduces the signal recorded in the optical disk 116. An error detection, correction, and compensation circuit 120 removes parity which is added to the digital data after demodulation at the error detection and correction code adding circuit 112. The compensation circuit 120 also corrects and compensates the data if there is an error. A block synthesizing circuit 124 synthesizes the decoded data for every block into video data before the data is divided by block dividing circuit 102.
In the recorder side shown in FIG. 1, a video signal applied to an input terminal 128 after being sampled and quantized, is divided into very small blocks composed of a plurality of picture elements of, for example, 64 picture elements of 8 horizontal picture elements by 8 vertical picture elements, at the block dividing circuit 102. The orthogonal transformer 103 orthogonally transforms every divided block. As a result, transformation coefficients corresponding to the number of picture elements in the block are produced. The transformation coefficients are quantized at quantizer 104. The quantized transformation coefficients are encoded as a variable length code in variable length encoder 105.
Parity for error correction is added to the output of the variable length encoder 105 at the error detection and correction code adding circuit 112. Then, the output of the error detection and correction code adding circuit 112 is digitally modulated, such as 8 to 14 modulation, at modulator 113. The output of modulator 113 is amplified at the recording amplifier 114 and the output of the recording amplifier 114 is recorded in optical disk 116 through recording head 115.
In the player side shown in FIG. 2, the digital data read from the optical disk 116 through the reproducing head 117 is digitally demodulated at the demodulator 119 after being amplified at the reproducing amplifier 118. The error detection, correction and compensation circuit 120 detects parity for error correction from the digital data after demodulation, removes it, and corrects and compensates errors in the digital data by calculation when an error is detected. For example, this is accomplished by examining the remainder of a demodulated code which has been divided by a generated polynomial expression. If the remainder is not zero, an error exists and the bit position is calculated using the remainder. Then, the bit is reversed. The output of the error detection, correction and compensation circuit 120 is decoded to produce a code with variable length at the variable length decoder 121. Then, the variable length code is inversely quantized at reverse quantizer 122. The digital data after inverse quantization is then provided to the reverse orthogonal transformer 123 to perform a reverse-orthogonal transformation for every block. Digital data decoded for each block is synthesized at the block synthesizing circuit 124 and supplied from output terminal 129 as a quantized decoded video signal.
In the above-mentioned configuration, however, where an encoded high definition television signal is recorded in the optical disk, only the decoded high definition television signal is obtained at the player side. That is, no standard system television signal is obtained. Therefore, the apparatus is not compatible with a standard television system. As a result, separate circuits are required for a high definition television signal and for a standard system television signal. Furthermore, when a digital video signal encoded and recorded on one optical disk separates video signals for both the right eye and left eye, only a united decoded video signal for the right eye and the left eye are obtained at the player side. That is, neither of the decoded video signals for the right eye and the left eye is obtained.